362
ORGANIC SYNTHESIS—1995
VI.A.9-8 Baldwin, J.E. et al., JCS(Pl), 1697.
Bu 3 Sn
OH
proton sponge
triphosgene, Et20
O
X
Bu 3 Sn
C r X l
- A A R
59-81 %
VLA.9-9 Hoffmann, H.M.R. et al., CB, 127, 1275; Takeda, K. et al., S,
1063.
4^° { R-XH, rt,
O
O
CH 2 CI 2
-O
X = N, O
74-98 %
VLA.9-10 Sugi, Y. et al., SL, 515 and CC, 1553.
Ph / ^ B r
A r
:
0 H
'
c
n °,!'
d C
'
2
. m.dppp, DBU
/
^
0-98 %
VI.A.9-11 Tsunoi, S., Ryu, I. and Sonoda, N., JACS, 116, 5473.
R l s
R2'
OH
"R3
O
CO, LTA, Ph-Me
V s f O
40°C, 3d
I I
R 2 ^ ^ R 3
38-71 %